Use Linux? Stop what you’re doing and apply this patch

Dating back to the release of glibc 2.9 in 2008, CVE-2015-7547 is a stack-based buffer overflow bug in the glibc DNS client-side resolver that opens the door to remote code execution when a particular library function is used. Software using the function can be exploited with attacker-controlled domain names, attacker-controlled DNS servers or man-in-the-middle attacks.